cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A089674 a(n) = number of n X n (0,1) matrices A such that the 2n+2 vectors consisting of the rows and the columns of the matrix A, as well as the main diagonal read in the upward direction and the main antidiagonal, are all distinct.

Original entry on oeis.org

0, 0, 0, 1692, 2329280, 13441654352, 190945826194432
Offset: 1

Views

Author

Vladeta Jovovic, Jan 04 2004

Keywords

Crossrefs

Binary matrices with distinct rows and columns, various versions: A059202, A088309, A088310, A088616, A089673, A089674, A093466, A094000, A094223, A116532, A116539, A181230, A259763

Extensions

a(6)-a(7) from Bert Dobbelaere, May 05 2025

A094223 Number of binary n X n matrices with all rows (columns) distinct, up to permutation of columns (rows).

Original entry on oeis.org

1, 2, 7, 68, 2251, 247016, 89254228, 108168781424, 451141297789858, 6625037125817801312, 348562672319990399962384, 66545827618461283102105245248, 46543235997095840080425299916917968, 120155975713532210671953821005746669185792, 1152009540439950050422144845158703009569109376384
Offset: 0

Views

Author

Goran Kilibarda and Vladeta Jovovic, May 28 2004

Keywords

Crossrefs

Main diagonal of A059584 and A059587, A060690, A088309.
Binary matrices with distinct rows and columns, various versions: A059202, A088309, A088310, A088616, A089673, A089674, A093466, A094000, A094223, A116532, A116539, A181230, A259763

Programs

  • Mathematica
    a[n_] := Sum[(-1)^(n - k)*StirlingS1[n, k]*Binomial[2^k, n], {k, 0, n}]; (* or *) a[n_] := Sum[ StirlingS1[n, k]*Binomial[2^k + n - 1, n], {k, 0, n}]; Table[ a[n], {n, 0, 12}] (* Robert G. Wilson v, May 29 2004 *)
  • PARI
    a(n) = sum(k=0, n, stirling(n, k, 1)*binomial(2^k+n-1, n)); \\ Michel Marcus, Dec 17 2022

Formula

a(n) = Sum_{k=0..n} (-1)^(n-k)*Stirling1(n, k)*binomial(2^k, n).
a(n) = Sum_{k=0..n} Stirling1(n, k)*binomial(2^k+n-1, n).

Extensions

More terms from Robert G. Wilson v, May 29 2004
a(13) onwards from Andrew Howroyd, Jan 20 2024

A000410 Number of singular n X n rational (0,1)-matrices.

Original entry on oeis.org

0, 0, 6, 425, 65625, 27894671, 35716401889, 144866174953833
Offset: 1

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Author

Keywords

Comments

Number of all n X n (0,1)-matrices having distinct, nonzero ordered rows and determinant 0 - compare A000409.
a(n) is the number of singular n X n rational {0,1}-matrices with no zero rows and with all rows distinct, up to permutation of rows and so a(n) = binomial(2^n-1,n) - A088389(n). Cf. A116506, A116507, A116527, A116532. - Vladeta Jovovic, Apr 03 2006

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Formula

n! * a(n) = A046747(n) - 2^(n^2) + n! * binomial(2^n -1, n).

Extensions

n=7 term from Guenter M. Ziegler (ziegler(AT)math.TU-Berlin.DE)
a(8) from Vladeta Jovovic, Mar 28 2006

A116506 Number of singular n X n rational {0,1}-matrices with no zero rows.

Original entry on oeis.org

0, 3, 169, 28065, 16114831, 33686890209, 262530190180063, 7717643584470877185
Offset: 1

Views

Author

Vladeta Jovovic, Apr 03 2006

Keywords

Crossrefs

Formula

a(n) = A055601(n) - A055165(n).

A116527 Number of singular n X n rational {0,1}-matrices with no zero rows or columns and with all rows distinct and all columns distinct, up to permutation of rows.

Original entry on oeis.org

0, 0, 0, 75, 22365, 13303500, 21058940420, 98692672142610
Offset: 1

Views

Author

Vladeta Jovovic, Apr 03 2006

Keywords

Crossrefs

Formula

a(n) = A094000(n) - A088389(n).
Conjecture: a(n) = A000410(n) - A000409(n-1) for n>1. - Jean-François Alcover, Jan 08 2020

A116507 Number of singular n X n rational {0,1}-matrices with no zero rows or columns.

Original entry on oeis.org

0, 1, 91, 18943, 12483601, 28530385447, 235529139302185, 7183142489571818623
Offset: 1

Views

Author

Vladeta Jovovic, Apr 03 2006

Keywords

Crossrefs

Formula

a(n) = A048291(n) - A055165(n).
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